[Libsysio-commit] HEAD: libsysio/include sysio.h

[Lee W. <lw...@us...>]

Update of /cvsroot/libsysio/libsysio/include
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv17693

Modified Files:
	sysio.h 
Log Message:


Work on SYSIO_INTERFACE_{DISPLAY_BLOCK,ENTER,RETURN}:

+ Cleaned up to parse correctly when expressions are used as args
+ Formatted to match *most* of the current style
+ RETURN now *sets* errno on error instead of simply restoring on no error.


Index: sysio.h
===================================================================
RCS file: /cvsroot/libsysio/libsysio/include/sysio.h,v
retrieving revision 1.20
retrieving revision 1.21
diff -u -w -b -B -p -r1.20 -r1.21
--- sysio.h	27 Apr 2004 22:13:01 -0000	1.20
+++ sysio.h	28 Apr 2004 10:53:01 -0000	1.21
@@ -352,6 +352,15 @@ extern int SYSIO_INTERFACE_NAME(umount)(
 
 /*
  * SYSIO interface frame macros
+ *
+ * + DISPLAY_BLOCK; Allocates storage on the stack for use by the set of
+ *	macros.
+ * + ENTER; Performs entry point work
+ * + RETURN; Returns a value and performs exit point work
+ *
+ * NB: For RETURN, the arguments are the return value and value for errno.
+ * If the value for errno is non-zero then that value, *negated*, is set
+ * into errno.
  */
 #define SYSIO_INTERFACE_DISPLAY_BLOCK                                  \
 	int _saved_errno;
@@ -363,7 +372,7 @@ extern int SYSIO_INTERFACE_NAME(umount)(
 #define SYSIO_INTERFACE_RETURN(rtn, err)                               \
 	do {                                                           \
 		SYSIO_LEAVE;                                           \
-		if (err == 0) errno = _saved_errno;                    \
+		errno = (err) ? -(err) : _saved_errno; \
 		return (rtn);                                          \
 	} while(0)